Computing devices are being used for a variety of tasks. Sometimes, a computing device or an application running on the computing device can detect and track a user's fingertip position. For example, a game application can track the position of the user's fingertip as he/she moves his/her finger. The movements of the fingertip tracked by the game can cause the game to provide responses accordingly. In another example, a computing device can track the position of the user's fingertip such that the fingertip can function as a pointer tool. When the user moves his/her fingertip, a cursor can move correspondingly on the screen of the computing device. However, conventional approaches generally detect and track the user's fingertip using a camera. If the user moves his/her fingertip out of the area viewable by the camera, then the fingertip position detection and tracking can function improperly, which will take away from the general user experience.